The Canadian government can't compel companies, who have no hardware in Canada, to comply with Canadian law. Proton Mail has already made a statement that they will not comply with any foreign anti-privacy laws.

At most, Canada could force Canadian ISPs to block connections to known 'offenders' like Proton or other non-compliant VPNs. Then it's a cat and mouse game of using different and new VPNs to access to safe, non-compliant, services.

You could also rent a VPS in Europe to act as your own private tunnel but there's no telling if or when that would be blocked.